When you lose weight, you breathe off 84 percent of the lost fat weight as carbon dioxide from your lungs and lose 16 percent as water in your urine. The lost fat is not lost as heat. It is not converted to muscle, and you do not lose weight from your bowel movements (The British Medical Journal, December 16, 2014).

Matter cannot be destroyed. It can only be altered. So in every chemical reaction, you have to have the same number of atoms after the reaction that you had before the reaction. Your body stores fat as triglycerides in fat cells and other tissues. The triglycerides that form body fat combine with oxygen to be converted to carbon dioxide plus water and generate heat.

Triglycerides + Oxygen = CO2 + Water + Heat

To lose 10 kilograms (22 pounds) of body fat, you need to breathe in 29 kg of oxygen, and breathe out 28 kg of carbon dioxide (CO2) and lose 11 kg of water (H2O).

Why You Need to Restrict Calories to Lose Weight
If you want to lose weight, you have to exercise more or eat less. Exercising without reducing calories rarely helps people to lose weight and keep it off. Successful weight-loss programs require taking in fewer calories as well as moving more. You can markedly reduce the absorption of calories from food by not cooking, grinding, cutting or chewing food excessively. You can also increase the number of calories burned by exercising longer and harder and moving more rather than sitting or lying in one place for extended periods of time.

How You Prepare Food Affects How Many Calories You Absorb
You can lose weight by eating foods that are absorbed poorly from your intestinal tract, such as high-fiber fruits, vegetables, nuts and seeds, and eating less of foods that are more readily absorbed such as those made with added sugar or flour. You can also reduce the calories that you get from food by eating it raw rather than cooked, and whole rather than ground, juiced or pulverized.

Raw Starches are Poorly Absorbed
Many of the most abundant plants on earth are poorly digested by humans in their raw state. However, cooking softens hard seeds, breaks down toxic and irritating substances in roots and leaves, and releases nutrients bound up in plant cells. Raw starchy root vegetables such as potatoes, turnips, cassava, yams and rutabagas are very low in calories. Boiling, baking or frying them markedly increases their calories, and the longer you cook them, the more calories they provide. Starchy foods such as potatoes, whole grains, beans and cassavas have 75-100 percent more digestible calories when they are cooked than when eaten raw.

Root vegetables are low in fiber and high in starches. Cooking turns these poorly absorbed starches into sugars that are readily absorbed in your intestines. Starches in root vegetables such as potatoes or in whole grains such as wheat are composed mostly of multi-sugar molecules called amylopectin and amylose. Your digestive enzymes have great difficulty breaking them down. Cooking gelatinizes starches so they are easily exposed to intestinal enzymes that break them down so they are readily absorbed.

Flour Makes You Fatter
Whole grains such as wheat, rye, barley and quinoa are seeds of grasses. These seeds have tight capsules that cannot be broken down by the enzymes in your intestines so they are hard to absorb. However, if you grind a whole grain into flour, it is easily absorbed. Cooking the flour increases the calories you absorb even more.

Soft Foods Yield More Calories
After 22 weeks, rats who ate uncooked cereals that were softened by being puffed with air were six percent heavier and had 30 percent more abdominal fat than rats who had been fed hard cereal pellets (Journal of Dental Research, 2003;82:491-494). This is a sign of higher blood sugar and insulin levels and risk for diabetes. Researchers showed that the rats fed hard food had a higher rise in body temperature after meals because they used significant energy in the act of chewing and digesting the food. The hard-pellet rats also had nearly twice the volume of feces, showing that they had absorbed far less of their food.

Absorption of Protein
When you eat meat, you eat mostly muscle which is made of very poorly absorbed collagen. If you ate raw, un-ground meat you would get very few calories from it. Cooking meat causes the muscle fibers to loosen and separate, making it easier to chew and digest. It also changes the structure of the proteins, causing them to unwind and become more susceptible to intestinal enzymes that break down protein to increase absorption.

However, cooking kills most of the parasites and bacteria that flourish in raw flesh and can be deadly to humans. Cooking allows humans to eat animal products more safely. A dog can eat food right out of the garbage can because dogs and wolves have the most acidic stomachs of all mammals and their stomach acids kill most germs. If you eat spoiled meat, you can get an infection and die.

Grinding meat into hamburger markedly increases absorption and reduces the amount of time you have to chew it. Organ meats such as kidneys, liver and brains are also easier to digest because they are low in collagen so you do not have to chew them as long as when you eat muscle.

Body Builders and Raw Eggs
Many body builders and weight lifters eat raw eggs with the mistaken belief that raw eggs grow larger muscles. When you eat uncooked eggs, you absorb less than 50 percent of their protein. When you eat cooked eggs, you absorb up to 95 percent. Heat denatures protein so that the protein molecules swell and are more exposed to the intestinal enzymes that separate proteins into their building blocks called amino acids. You then absorb a much greater percentage of the protein because amino acids, not whole protein, pass into your bloodstream.

Preparing Foods to Help You Lose Weight
If you are trying to lose weight, eat more foods that are not cooked, chopped, ground or softened in any way.
• Eat lots of raw fruits and vegetables.
• You can eat cooked fruits and non-starchy vegetables also, because they are usually low in calories even when cooked.
• Eat WHOLE grains, beans, seeds and nuts that have not been ground into flour.
• Restrict sugared drinks because virtually 100 percent of their calories are rapidly absorbed.
• Restrict all sugar-added foods.
• Restrict foods made from flour such as bakery products and pastas.

About the Author: Gabe Mirkin, MD

Sports medicine doctor, fitness guru and long-time radio host Gabe Mirkin, M.D., brings you news and tips for your healthful lifestyle. A practicing physician for more than 50 years and a radio talk show host for 25 years, Dr. Mirkin is a graduate of Harvard University and Baylor University College of Medicine. He is board-certified in four specialties: Sports Medicine, Allergy and Immunology, Pediatrics and Pediatric Immunology. The Dr. Mirkin Show, his call-in show on fitness and health, was syndicated in more than 120 cities.
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